BACKGROUND
Field
[0001] The invention generally relates to a sensing driving circuit and a display device
having the sensing driving circuit.
Description of the Related Technology
[0002] Generally, a display device includes a display panel and a driving unit. The display
panel includes a plurality of scan lines, a plurality of data lines, and a plurality
of pixels. The driving unit includes a scan driving circuit providing scan signals
to the scan lines and a data driving circuit providing data signals to the data lines.
[0003] Pixels in a display device degrade with usage, and characteristics of the pixel such
as luminance can be impacted. Various methods of sensing and measuring the change
in pixel characteristics and compensating for the change are undergoing research.
SUMMARY OF CERTAIN INVENTIVE ASPECTS
[0004] The invention seeks to provide a sensing driving circuit that can selectively output
sensing signals.
[0005] The invention also seeks to provide a display device that can measure a characteristic
change of a pixel.
[0006] Accordingly, the invention provides a sensing driving circuit that includes a plurality
of stages outputting a plurality of sensing signals, respectively. A (K)th stage of
the stages can include a shift register unit configured to provide a (K)th carry signal
to a next stage of the (K)th stage and a masking buffer unit configured to output
a (K)th sensing signal of the sensing signals. The masking buffer unit can include
a first input part configured to apply an input signal to a first node in response
to a node driving signal, and to apply a first power voltage to a second node in response
to the input signal and the node driving signal, a node masking part configured to
apply the first power voltage to the first node in response to a masking signal, and
to apply a second power voltage to the second node in response to the masking signal,
a sensing pull-up part configured to pull up the (K)th sensing signal in response
to a second node signal of the second node, and a sensing pull-down part configured
to pull down the (K)th sensing signal in response to a first node signal of the first
node, where K is an integer greater than 0.
[0007] In example embodiments, the first input part includes a first input transistor, a
second input transistor, and a third input transistor. The first input transistor
can include a gate electrode to which the input signal is applied, a first electrode
to which the first power voltage is applied, and a second electrode connected to a
first electrode of the second input transistor. The second input transistor can include
a gate electrode to which the node driving signal is applied, the first electrode
connected to the second electrode of the first input transistor, and a second electrode
connected to the second node. The third input transistor can include a gate electrode
to which the node driving signal is applied, a first electrode to which the input
signal is applied, and a second electrode connected to the first node.
[0008] In example embodiments, the node masking part includes a first masking transistor
and a second masking transistor. The first masking transistor can include a gate electrode
to which the masking signal is applied, a first electrode to which the first power
voltage applied, and a second electrode connected to the first node. The second masking
transistor can include a gate electrode to which the masking signal applied, a first
electrode to which a second power voltage is applied, and a second electrode connected
to the second node.
[0009] In example embodiments, the sensing pull-up part includes a first full-up transistor
and a first capacitor.
[0010] In example embodiments, the first full-up transistor includes a gate electrode connected
to the second node, a first electrode to which the first power voltage is applied,
and a second electrode connected to a sensing signal output terminal outputting the
(K)th sensing signal. The first capacitor can include a first electrode connected
to the second node, and a second electrode to which the first power voltage is applied.
[0011] In example embodiments, the first full-up transistor includes a gate electrode connected
to the second node, a first electrode to which a simultaneous driving signal, and
a second electrode connected to a sensing signal output terminal outputting the
[0012] (K)th sensing signal. The first capacitor can include a first electrode connected
to the second node, and a second electrode to which the simultaneous driving signal
is applied.
[0013] In example embodiments, the sensing pull-down part includes a first full-down transistor,
and a second capacitor. The first full-down transistor can include a gate electrode
connected to the first node, a first electrode to which a first clock signal is applied,
and a second electrode a sensing signal output terminal outputting the (K)th sensing
signal. The second capacitor can include a first electrode connected to the first
node, and a second electrode connected to the sensing signal output terminal.
[0014] In example embodiments, the shift register unit includes a second input part configured
to apply the input signal to a third node in response to a second clock signal, a
third input part configured to apply the second clock signal to a fourth node in response
to a third node signal of the third node, a carry pull-up part configured to pull
up the (K)th carry signal in response to the fourth node signal, a carry pull-down
part configured to pull down the (K)th carry signal in response to the third node
signal, a holding part configured to maintain the fourth node signal in response to
the second clock signal, and a stabilizing part configured to stabilize the (K)th
carry signal in response to the fourth node signal and a first clock signal.
[0015] In example embodiments, the second input part includes a fourth input transistor.
The fourth input transistor can include a gate electrode to which the second clock
signal is applied, a first electrode to which the input signal is applied, and a second
electrode connected to the third node.
[0016] In example embodiments, the third input part includes a fifth input transistor. The
fifth input transistor can include a gate electrode to which the third node signal
is applied, a first electrode to which the second clock signal is applied, and a second
electrode connected to the fourth node.
[0017] In example embodiments, the carry pull-up part includes a second pull-up transistor
and a third capacitor. The second pull-up transistor can include a gate electrode
connected to the fourth node, a first electrode to which the first power voltage is
applied, and a second electrode connected to a carry signal output terminal outputting
the (K)th carry signal. The third capacitor can include a first electrode connected
to the fourth node, and a second electrode to which the first power voltage is applied.
[0018] In example embodiments, the carry pull-down part includes a second pull-down transistor
and a fourth capacitor. The second pull-down transistor can include a gate electrode
connected to the third node, a first electrode to which a first clock signal is applied,
and a second electrode connected to a carry signal output terminal outputting the
(K)th carry signal. The fourth capacitor can include a first electrode connected to
the third node, and a second electrode connected to the carry signal output terminal.
[0019] In example embodiments, the holding part includes a holding transistor. The holding
transistor can include a gate electrode to which the second clock signal is applied,
a first electrode to which the second clock signal is applied, and a second electrode
connected to the fourth node.
[0020] In example embodiments, the stabilizing part includes a first stabilizing transistor
and a second stabilizing transistor. The first stabilizing transistor can include
a gate electrode to which the first clock signal is applied, a first electrode connected
to the third node, and a second electrode connected to a first electrode of the second
stabilizing transistor. The second stabilizing transistor can include a gate electrode
connected to the fourth node, the first electrode connected to the second electrode
of the first stabilizing transistor, and the second electrode connected to a carry
signal output terminal outputting the (K)th carry signal.
[0021] Another aspect of the invention provides a display device that includes a display
panel including a plurality of scan lines, a plurality of sensing lines, a plurality
of data lines, and a plurality of pixels, a data driving circuit configured to output
a plurality of data signals to the data lines, respectively, a scan driving circuit
configured to output a plurality of scan signals to the scan lines, respectively,
a sensing driving circuit including a plurality of stages outputting a plurality of
sensing signals for measuring a characteristic change of the pixels to the sensing
lines, respectively, and a controller configured to control the data driving circuit,
the scan driving circuit, and the sensing driving circuit. A (K)th stage of the stages
can include a shift register unit configured to provide a (K)th carry signal to a
next stage of the (K)th stage, and a masking buffer unit configured to output a (K)th
sensing signal of the sensing signals. The masking buffer unit can include a first
input part configured to apply an input signal to a first node in response to a node
driving signal, and to apply a first power voltage to a second node in response to
the input signal and the node driving signal, a node masking part configured to apply
the first power voltage to the first node in response to a masking signal, and to
apply a second power voltage to the second node in response to the masking signal,
a sensing pull-up part configured to pull up the (K)th sensing signal in response
to a second node signal of the second node, and a sensing pull-down part configured
to pull down the (K)th sensing signal in response to a first node signal of the first
node, where K is an integer greater than 0.
[0022] In example embodiments, the scan driving circuit sequentially outputs the scan signals
to the scan lines in a display period. The sensing driving circuit can output at least
one of the sensing signals to at least one of the sensing lines in a sensing period.
[0023] In example embodiments, the controller measures a magnitude of the characteristic
change for at least one of the pixels to which the sensing signals are applied in
the sensing period.
[0024] In example embodiments, the controller compensates input image data based on the
characteristic change to adjust the data signals.
[0025] In example embodiments, the sensing driving circuit outputs the sensing signals that
have the same phase to the sensing lines in an initialization period of the display
panel.
[0026] In example embodiments, the shift register unit includes a second input part configured
to apply the input signal to a third node in response to a second clock signal, a
third input part configured to apply the second clock signal to a fourth node in response
to a third node signal of the third node, a carry pull-up part configured to pull
up the (K)th carry signal in response to the fourth node signal, a carry pull-down
part configured to pull down the (K)th carry signal in response to the third node
signal, a holding part configured to maintain the fourth node signal in response to
the second clock signal, and a stabilizing part configured to stabilize the (K)th
carry signal in response to the fourth node signal and a first clock signal.
[0027] Another aspect of the invention provides a sensing driving circuit for a display
device, comprising: a plurality of stages configured to respectively output a plurality
of sensing signals and including a (K)th stage and a (K+1)th stage. The (K)th stage
comprises a shift register configured to provide a (K)th carry signal to the (K+1)th
stage; and a masking buffer configured to output a (K)th sensing signal. The masking
buffer includes: a first input circuit configured to provide i) an input signal to
a first node based on a node driving signal and ii) a first power voltage to a second
node based on the input signal and the node driving signal; a node masking circuit
configured to supply the first power voltage to the first node based on a masking
signal, and supply a second power voltage to the second node based on the masking
signal; a sensing pull-up circuit configured to pull up the (K)th sensing signal based
on a second node signal of the second node; and a sensing pull-down circuit configured
to pull down the (K)th sensing signal based on a first node signal of the first node,
where K is an integer greater than 0.
[0028] In example embodiments, the first input circuit includes: a first input transistor
including a gate electrode configured to receive the input signal, a first electrode
configured to receive the first power voltage, and a second electrode; a second input
transistor including a gate electrode configured to receive the node driving signal,
a first electrode electrically connected to the second electrode of the first input
transistor, and a second electrode electrically connected to the second node; and
a third input transistor including a gate electrode configured to receive the node
driving signal, a first electrode configured to receive the input signal, and a second
electrode electrically connected to the first node.
[0029] In example embodiments, the node masking circuit includes: a first masking transistor
including a gate electrode configured to receive the masking signal, a first electrode
configured to receive the first power voltage, and a second electrode electrically
connected to the first node; and a second masking transistor including a gate electrode
configured to receive the masking signal, a first electrode configured to receive
a second power voltage, and a second electrode electrically connected to the second
node.
[0030] In example embodiments, the sensing pull-up circuit includes a first full-up transistor
and a first capacitor.
[0031] In example embodiments, the first full-up transistor includes a gate electrode electrically
connected to the second node, a first electrode configured to receive the first power
voltage, and a second electrode electrically connected to a sensing signal output
terminal configured to output the (K)th sensing signal, wherein the first capacitor
includes a first electrode electrically connected to the second node and a second
electrode configured to receive the first power voltage.
[0032] In example embodiments, the first full-up transistor includes a gate electrode electrically
connected to the second node, a first electrode configured to receive a global driving
signal, and a second electrode electrically connected to a sensing signal output terminal
configured to output the (K)th sensing signal, wherein the first capacitor includes
a first electrode electrically connected to the second node and a second electrode
configured to receive the global driving signal.
[0033] In example embodiments, the sensing pull-down circuit includes: a first full-down
transistor including a gate electrode electrically connected to the first node, a
first electrode configured to receive a first clock signal, and a second electrode
electrically connected to a sensing signal output terminal configured to output the
(K)th sensing signal; and a second capacitor including a first electrode electrically
connected to the first node and a second electrode electrically connected to the sensing
signal output terminal.
[0034] In example embodiments, the shift register includes: a second input circuit configured
to provide the input signal to a third node based on a second clock signal; a third
input circuit configured to provide the second clock signal to a fourth node based
on a third node signal of the third node; a carry pull-up circuit configured to pull
up the (K)th carry signal based on the fourth node signal; a carry pull-down circuit
configured to pull down the (K)th carry signal based on the third node signal; a holding
circuit configured to maintain the fourth node signal based on the second clock signal;
and a stabilizing circuit configured to stabilize the (K)th carry signal based on
the fourth node signal and a first clock signal.
[0035] In example embodiments, the second input circuit includes a fourth input transistor
including a gate electrode configured to receive the second clock signal, a first
electrode configured to receive the input signal, and a second electrode electrically
connected to the third node.
[0036] In example embodiments, the third input circuit includes a fifth input transistor
including a gate electrode configured to receive the third node signal, a first electrode
configured to receive the second clock signal, and a second electrode electrically
connected to the fourth node.
[0037] In example embodiments, the carry pull-up circuit includes; a second pull-up transistor
including a gate electrode electrically connected to the fourth node, a first electrode
configured to receive the first power voltage, and a second electrode electrically
connected to a carry signal output terminal configured to output the (K)th carry signal;
and a third capacitor including a first electrode electrically connected to the fourth
node and a second electrode configured to receive the first power voltage.
[0038] In example embodiments, the carry pull-down circuit includes: a second pull-down
transistor including a gate electrode electrically connected to the third node, a
first electrode configured to receive a first clock signal, and a second electrode
electrically connected to a carry signal output terminal configured to output the
(K)th carry signal; and a fourth capacitor including a first electrode electrically
connected to the third node and a second electrode electrically connected to the carry
signal output terminal.
[0039] In example embodiments, the holding circuit includes a holding transistor including
a gate electrode configured to receive the second clock signal, a first electrode
configured to receive the second clock signal, and a second electrode electrically
connected to the fourth node.
[0040] In example embodiments, the stabilizing circuit includes: a first stabilizing transistor
including a gate electrode configured to receive the first clock signal, a first electrode
electrically connected to the third node, and a second electrode; and a second stabilizing
transistor including a gate electrode electrically connected to the fourth node, a
first electrode electrically connected to the second electrode of the first stabilizing
transistor, and a second electrode electrically connected to a carry signal output
terminal configured to output the (K)th carry signal.
[0041] Another aspect of the invention provides a display device comprising: a display panel
including a plurality of scan lines, a plurality of sensing lines, a plurality of
data lines, and a plurality of pixels; a data driving circuit configured to output
a plurality of data signals respectively to the data lines; a scan driving circuit
configured to output a plurality of scan signals respectively to the scan lines; a
sensing driving circuit including a plurality of stages each configured to output
at least one of a plurality of sensing signals to at least one of the sensing lines
so as to measure a change in at least one characteristic of the pixels, wherein the
stages include a (K)th stage and a (K+1)th stage; and a controller configured to control
the data driving circuit, the scan driving circuit, and the sensing driving circuit.
The (K)th stage includes: a shift register configured to provide a (K)th carry signal
to the (K+1)th stage; and a masking buffer configured to output a (K)th sensing signal.
The masking buffer includes: a first input circuit configured to provide i) an input
signal to a first node based on a node driving signal and ii) a first power voltage
to a second node based on the input signal and the node driving signal; a node masking
circuit configured to supply the first power voltage to the first node based on a
masking signal, and to supply a second power voltage to the second node based on the
masking signal; a sensing pull-up circuit configured to pull up the (K)th sensing
signal based on a second node signal of the second node; and a sensing pull-down circuit
configured to pull down the (K)th sensing signal based on a first node signal of the
first node, where K is an integer greater than 0.
[0042] In example embodiments, the scan driving circuit is further configured to sequentially
output the scan signals to the scan lines in a display period, wherein the sensing
driving circuit is further configured to provide the at least one sensing signal to
the at least one sensing line in a sensing period.
[0043] In example embodiments, the controller is further configured to measure a magnitude
of the change in the characteristic of at least one of the pixels configured to receive
the at least one sensing signal.
[0044] In example embodiments, the controller is further configured to compensate input
image data based on the change in the characteristic of the pixels so as to adjust
the data signals.
[0045] In example embodiments, the sensing driving circuit is further configured to output
the sensing signals having the same phase to the sensing lines in an initialization
period of the display panel.
[0046] In example embodiments, the shift register includes: a second input circuit configured
to provide the input signal to a third node based on a second clock signal; a third
input circuit configured to provide the second clock signal to a fourth node based
on a third node signal of the third node; a carry pull-up circuit configured to pull
up the (K)th carry signal based on the fourth node signal; a carry pull-down circuit
configured to pull down the (K)th carry signal based on the third node signal; a holding
circuit configured to maintain the fourth node signal based on the second clock signal;
and a stabilizing circuit configured to stabilize the (K)th carry signal based on
the fourth node signal and a first clock signal.
[0047] At least some of the above and other features of the invention are set out in the
claims.
[0048] According to at least one of the disclosed embodiments, a sensing driving circuit
selectively outputs sensing signals without an additional decoder. The sensing driving
circuit can have a simple structure in comparison with a driving circuit including
the decoder.
[0049] In addition, a display device according to example embodiments can reduce power consumption
and manufacturing cost by including the sensing driving circuit. The display device
can have a narrow bezel because the sensing driving circuit is implemented in a small
scale.
BRIEF DESCRIPTION OF THE DRAWINGS
[0050]
FIG. 1 is a block diagram illustrating a display device according to example embodiments
of the invention.
FIG. 2 is a diagram illustrating an example of frame periods for the display device
of FIG. 1.
FIG. 3 is a circuit diagram illustrating an example of a pixel included in the display
device of FIG. 1.
FIG. 4 is a block diagram illustrating one example of a sensing driving circuit included
in the display device of FIG. 1.
FIG. 5 is a block diagram illustrating a shift register unit of a (K)th stage included
in the sensing driving circuit of FIG. 4.
FIG. 6 is a block diagram illustrating a masking buffer unit of a (K)th stage included
in the sensing driving circuit of FIG. 4.
FIG. 7 is a circuit diagram illustrating a (K)th stage included in the sensing driving
circuit of FIG. 4.
FIG. 8 is a waveform diagram for describing a sensing operation of the sensing driving
circuit of FIG. 4.
FIG. 9 is a block diagram illustrating another example of the sensing driving circuit
included in a display device of FIG. 1.
FIG. 10 is a block diagram illustrating a masking buffer unit of a (K)th stage included
in the sensing driving circuit of FIG. 9.
FIG. 11 is a circuit diagram illustrating a (K)th stage included in the sensing driving
circuit of FIG. 9.
FIG. 12 is a waveform diagram for describing an initialization operation of the sensing
driving circuit of FIG. 9 in an initialization period.
DETAILED DESCRIPTION
[0051] Embodiments of the invention will be described more fully hereinafter with reference
to the accompanying drawings, in which various embodiments are shown. In this disclosure,
the term "substantially" includes the meanings of completely, almost completely or
to any significant degree under some applications and in accordance with those skilled
in the art. Moreover, "formed on" can also mean "formed over." The term "connected"
can include an electrical connection.
[0052] Referring to FIG. 1, the display device 1000 includes a display panel 100, a scan
driving circuit 200, a data driving circuit 300, an emission driving circuit 400,
a sensing driving circuit 500, a power supply 800, and a controller 900. In some embodiments,
the display device 1000 is an organic light-emitting diode (OLED) display. Depending
on embodiments, certain elements may be removed from or additional elements may be
added to the display device 1000 illustrated in FIG. 1. Furthermore, two or more elements
may be combined into a single element, or a single element may be realized as multiple
elements. This applies to the remaining apparatus embodiments.
[0053] The display panel 100 can display an image. The display panel 100 can include a plurality
of scan lines SL1 through SLn, a plurality of sensing lines SE1 through SEn, a plurality
of emission lines EM1 through EMn, a plurality of data lines DL1 through DLm, and
a plurality of pixels PX. For example, the display panel 100 includes n*m pixels PX
because the pixels PX are arranged at locations corresponding to crossing points of
the scan lines SL1 through SLn and the data-lines DL1 through DLm.
[0054] The scan driving circuit 200 can provide a plurality of scan signals to the pixels
PX via the scan lines SL1 through SLn based on a first control signal CONT1 received
from the controller 900.
[0055] The data driving circuit 300 can provide a plurality of data signals to the pixels
PX via the data lines DL1 through DLm based on a second control signal CONT2 and output
image data DATA1 received from the controller 900.
[0056] The emission driving circuit 400 can provide a plurality of emission signals to the
pixels PX via the emission lines EM1 through EMn based on a third control signal CONT3
received from the controller 900.
[0057] The sensing driving circuit 500 can output at least one of the sensing signals to
at least one of the sensing lines SE1 through SEn in a sensing period based on a fourth
control signal CONT4 received from the controller 900. The sensing driving circuit
500 can include a plurality of stages. Each of the stages can output the sensing signal
to measure a characteristic change of the pixel PX. In some embodiments, the sensing
driving circuit 500 outputs the sensing signals that have substantially the same phase
to the sensing lines SE1 through SEn in an initialization period to initialize the
display panel 100. One pixel characteristic is luminance, but is not limited thereto.
[0058] A (K)th stage included in the sensing driving circuit 500 can include a shift register
unit and a masking buffer unit, where K is an integer greater than 0. The shift register
unit can provide a (K)th carry signal to a next stage of the (K)th stage (e.g., the
(K+1)th stage). The masking buffer unit can output a (K)th sensing signal. In some
embodiments, the masking buffer unit includes a first input part or first input circuit
applying an input signal to a first node in response to a node driving signal and
applying a first power voltage to a second node in response to the input signal and
the node driving signal, a node masking part or node masking circuit applying the
first power voltage to the first node in response to a masking signal and applying
a second power voltage to the second node in response to the masking signal, a sensing
pull-up part or sensing pull-up circuit pulling up the (K)th sensing signal in response
to a second node signal of the second node, and a sensing pull-down part or sensing
pull-down circuit pulling down the (K)th sensing signal in response to a first node
signal of the first node. In some embodiments, the shift register unit includes a
second input part or second input circuit applying the input signal to a third node
in response to a second clock signal, a third input part or third input circuit applying
the second clock signal to a fourth node in response to a third node signal of the
third node, a carry pull-up part or carry pull-up circuit pulling up the (K)th carry
signal in response to the fourth node signal, a carry pull-down part or carry pull-down
circuit pulling down the (K)th carry signal in response to the third node signal,
a holding part or holding circuit maintaining the fourth node signal in response to
the second clock signal, and a stabilizing part or stabilizing circuit stabilizing
the (K)th carry signal in response to the fourth node signal and a first clock signal.
Hereinafter, the sensing driving circuit 500 will be described in detail with reference
to the FIGS. 4 through 7.
[0059] The power supply 800 can provide a high power voltage ELVDD, a low power voltage
ELVSS, and an initialization voltage VI to the pixels PX via power lines.
[0060] The controller 900 can control the scan driving circuit 200, the data driving circuit
300, the emission driving circuit 400, the sensing driving circuit 500, and the power
supply 800. The controller 900 can receive an input control signal CTL and input image
data DATA from an image source, such as an external graphic device. The input control
signal CTL can include a master clock signal, a vertical synchronization signal, a
horizontal synchronization signal, a data enable signal, etc. In addition, the controller
900 can generate the first control signal CTL1 based on the input control signal CTL
to control the scan driving circuit 200. Also, the controller 900 can generate the
output image data DATA1 based on the input image data DATA and can generate the second
control signal CTL2 based on the input control signal CTL to control the data driving
circuit 300. The controller 900 can generate the third control signal CTL3 based on
the input control signal CTL to control the emission driving circuit 400. The controller
900 can generate the fourth control signal CTL4 based on the input control signal
CTL to control the sensing driving circuit 500.
[0061] In some embodiments, the controller 900 measures a magnitude of the characteristic
change for the pixels PX. For example, the sensing driving circuit 500 outputs at
least one of the sensing signals to at least one of the sensing lines in the sensing
period. The controller 900 can measure a magnitude of the characteristic change for
at least one of the pixels to which the sensing signals are applied in the sensing
period. The controller 900 can compensate input image data DATA based on the characteristic
change to reduce a characteristic variation of the pixels PX. For example, the controller
900 stores the magnitude of the characteristic change for the pixels PX in the memory
device and compensate input image data DATA based on the magnitude of the characteristic
change stored in the memory device.
[0062] Therefore, the sensing driving circuit 500 can selectively output the sensing signals
without an additional decoder, thereby having a relatively simple structure. The sensing
driving circuit 500 can receive input signals of which number is relatively small
in comparison with a driving circuit including the decoder. Also, in some embodiments,
the sensing driving circuit 500 does not include a part in which a static current
flows. Therefore, the display device 1000 can reduce power consumption and manufacturing
cost by including the sensing driving circuit 500. Also, the display device 1000 can
have a narrow bezel because the sensing driving circuit 500 is implemented in a small
scale.
[0063] FIG. 2 is a diagram illustrating an example of frame periods for a display device
of FIG. 1.
[0064] Referring to FIG. 2, each frame period FRAME1, FRAME2 includes a display period D1,
D2 and a sensing period S1, S2.
[0065] In some embodiments, the display device is driven by a progressive emission technique.
In order that the display device displays an image using the progressive emission
technique, a scan driving circuit can sequentially provide scan signals to scan lines,
and each pixel can emit light corresponding to the scan signals in the display period
D1, D2. In some embodiments, the display device is driven by a simultaneous emission
technique, substantially simultaneous emission technique, or concurrent emission technique.
For example, the display period D1, D2 includes an initialization period, a scan period,
and an emission period. In order that the display device displays the image using
the simultaneous emission technique, the scan driving circuit can sequentially provide
the scan signals to the scan lines in the scan period, and each pixel can emit light
in the emission period.
[0066] The sensing driving circuit can output at least one of the sensing signals to at
least one of the sensing lines in the sensing period S1, S2. The sensing period S1,
S2 is for measuring a magnitude of the characteristic change for at least one of the
pixels. In order that the display device normally displays an image, a time length
of the sensing period S1, S2 can be relatively short in comparison with a time length
of the display period D1, D2. Thus, the sensing signal can be applied to at least
one selected from the sensing lines in each sensing period S1, S2. In some embodiments,
the sensing lines are sequentially selected in every frame period. In some embodiments,
the sensing lines are randomly selected.
[0067] For example, the sensing driving circuit outputs the sensing signal to the (X)th
sensing line located in the (X)th row in the first sensing period S1 of the first
frame period FRAME1. The controller can measure a characteristic change for the pixels
connected to the (X)th sensing line in the first sensing period S1 and can store the
characteristic change in a memory device. The sensing driving circuit can output the
sensing signal to the (Y)th sensing line located in the (Y)th row in the second sensing
period S2 of the second frame period FRAME2. The controller can measure a characteristic
change for the pixels connected to the (Y)th sensing line in the second sensing period
S2 and can store the characteristic change in a memory device.
[0068] Therefore, the controller can compensate input image data based on the characteristic
change, thereby reducing the characteristic variation of the pixels.
[0069] FIG. 3 is a circuit diagram illustrating an example of a pixel included in a display
device of FIG. 1.
[0070] Referring to FIG. 3, at least one of the sensing lines receives the sensing signal
in the sensing period. A characteristic change for the pixels PX connected to the
sensing lines that receive the sensing signal can be measured.
[0071] The pixel PX can include a plurality of transistors T1 through T8 and a capacitor
Cst. For example, a first transistor T1 is connected between a high power voltage
ELVDD and an anode electrode of the OLED. The first transistor T1 can apply a driving
current corresponding to a data signal to the OLED. A second transistor T2 can be
connected between a first electrode of the first transistor T1 and a data line DLj.
A third transistor T3 can be connected between a gate electrode and a second electrode
of the first transistor T1. A fourth transistor T4 can be connected between an initialization
voltage VI and the gate electrode of the first transistor T1. A fifth transistor T5
can be connected between the high power voltage ELVDD and the first electrode of the
first transistor T1. A sixth transistor T6 can be connected between the second electrode
of the first transistor T1 and the anode electrode of the OLED. A seventh transistor
T7 can be connected between the initialization voltage VI and the anode electrode
of the OLED. An eighth transistor T8 can be connected between the data line DLj and
the anode electrode of the OLED.
[0072] For example, the fourth transistor T4 applies the initialization voltage VI to the
capacitor Cst and the gate electrode of the first transistor T1 in response to the
(K-1)th scan signal so as to reset the capacitor Cst and the gate electrode of the
first transistor T1 as the initialization voltage VI. The seventh transistor T7 can
apply the initialization voltage VI to the anode electrode of the OLED in response
to the (K-1)th scan signal to reset the anode electrode of the OLED as the initialization
voltage VI.
[0073] The second transistor T2 can apply the data signal to the first transistor T1 in
response to the (K)th scan signal.
[0074] The third transistor T3 can compensate a threshold voltage of the first transistor
T1 in response to the (K)th scan signal by connecting the gate electrode and the second
electrode of the first transistor T1 (i.e., a diode connection of the first transistor
T1). Because the second transistor T2 and the third transistor T3 can receive the
(K)th scan signal, the data signal can be applied while the threshold voltage of the
first transistor T1 is compensated.
[0075] The first transistor T1 can provide the driving current corresponding to the data
signal to the OLED.
[0076] The sixth transistor T6 can be located between the second electrode of the first
transistor T1 and the anode electrode of the OLED. The sixth transistor T6 can control
light emission of the OLED in response to a (K)th emission signal.
[0077] The eighth transistor T8 can connect the anode electrode of the OLED to the data
line DLj in response to the (K)th sensing signal to measure the characteristic change
of the pixel PX.
[0078] FIG. 4 is a block diagram illustrating one example of a sensing driving circuit included
in a display device of FIG. 1.
[0079] Referring to FIG. 4, the sensing driving circuit 500A includes a plurality of stages
500A-1 through 500A-n that are dependently connected to each other. Each of the stages
500A-1 through 500A-n can include a shift register unit and a masking buffer unit.
Each of the shift register units 600A-1 through 600A-n can include an input terminal
IN, a second clock terminal CK, a first voltage terminal VGH, a second voltage terminal
VGL, and a carry signal output terminal CARRY. Each of the masking buffer units 700A-1
through 700A-n can include an input terminal IN, a first clock terminal CKB, a masking
terminal MASK, a node driving terminal SET, a first voltage terminal VGH, a second
voltage terminal VGL, and a sensing signal output terminal SEN.
[0080] An input signal can be applied to the input terminal IN. Here, the input signal can
be a sensing start signal SSP or a carry signal of the previous stage. Thus, the sensing
start signal SSP is applied to the input terminal IN of the first stage 500A-1. The
carry signals of the previous stages are respectively applied to each input terminal
IN of the second through (N)th stages 500A-2 through 500A-n.
[0081] A first sensing clock signal CLK1 or a second sensing clock signal CLK2 having different
timings can be applied to the first clock terminal CKB. For example, the second sensing
clock signal CLK2 is a signal inverted from the first sensing clock signal CLK1. In
adjacent stages, the first sensing clock signal CLK1 and the second sensing clock
signal CLK2 can be applied to the first clock terminal CKB in opposite sequences.
For example, the second sensing clock signal CLK2 is applied to the first clock terminal
CKB of odd-numbered stages 500A-1, 500A-3, .... In contrast, in this example, the
first sensing clock signal CLK1 is applied to the first clock terminal CKB of even-numbered
stages 500A-2,500A-4, ....
[0082] A first sensing clock signal CLK1 or a second sensing clock signal CLK2 having different
timings can be applied to the second clock terminal CK. In adjacent stages, the first
sensing clock signal CLK1 and the second sensing clock signal CLK2 can be applied
to the second clock terminal CK in opposite sequences. For example, the first sensing
clock signal CLK1 is applied to the second clock terminal CK of odd-numbered stages
500A-1, 500A-3, .... In contrast, in this example, the second sensing clock signal
CLK2 is applied to the second clock terminal CK of even-numbered stages 500A-2, 500A-4,
....
[0083] A node driving signal can be applied to the node driving terminal SET. The node driving
signal is for controlling the first node and the second node of the masking buffer
unit. For example, the node driving signal is applied to the node driving terminal
SET at a start point of the sensing period.
[0084] A masking signal can be applied to the masking terminal MASK. The masking signal
is for masking the first node and the second node of the masking buffer unit. For
example, the masking signal is inactivated at the start point of the sensing period.
[0085] A first voltage VDD can be provided to the first voltage terminal VGH. For example,
the first voltage VDD is a high level voltage.
[0086] A second voltage VSS can be provided to the second voltage terminal VGL. For example,
the second voltage VSS is a low level voltage.
[0087] A carry signal can be outputted to an input terminal IN of the next stage via the
carry signal output terminal CARRY. For example, the first carry signal is outputted
to the input terminal IN of the second stage 500A-2 via the carry signal output terminal
CARRY of the first stage 500A-1.
[0088] A sensing signal can be outputted to a sensing line via the sensing signal output
terminal SEN. For example, the sensing start signal SSP is adjusted to select some
of the sensing lines for measuring the characteristic change or the deterioration
of the pixel in the sensing period. Therefore, the sensing signals can be outputted
by aimed stages in the sensing period by controlling the masking signal and the node
driving signal.
[0089] FIG. 5 is a block diagram illustrating a shift register unit of a (K)th stage included
in a sensing driving circuit of FIG. 4. FIG. 6 is a block diagram illustrating a masking
buffer unit of a (K)th stage included in a sensing driving circuit of FIG. 4. FIG.
7 is a circuit diagram illustrating a (K)th stage included in a sensing driving circuit
of FIG. 4.
[0090] Referring to FIGS. 5 through 7, the (K)th stage 500A-k included in the sensing driving
circuit includes a shift register unit or shift register 600A-k and a masking buffer
unit or masking buffer 700A-k.
[0091] The shift register unit 600A-k can provide a (K)th carry signal CARRY[K] to a next
stage of the (K)th stage 500A-k. The shift register unit 600A-k can include a second
input part 610, a third input part 620, a carry pull-up part 630, a carry pull-down
part 640, a holding part 650, and a stabilizing part 660.
[0092] The second input part 610 can apply the input signal to a third node N3 in response
to the second clock signal CK. Thus, the second input part 610 can apply the sensing
start signal SSP or the carry signal of previous stage CARRY[K-1] to the third node
N3 in response to the second clock signal CK. In some embodiments, the second input
part 610 includes a fourth input transistor TR2. The fourth input transistor TR2 can
include a gate electrode to which the second clock signal CK is applied, a first electrode
to which the input signal is applied, and a second electrode connected to the third
node N3.
[0093] The third input part 620 can apply the second clock signal CK to a fourth node N4
in response to a third node signal of the third node N3. In some embodiments, the
third input part 620 includes a fifth input transistor TR1. The fifth input transistor
TR1 can include a gate electrode to which the third node signal is applied, a first
electrode to which the second clock signal CK is applied, and a second electrode connected
to the fourth node N4.
[0094] The carry pull-up part 630 can pull up the (K)th carry signal CARRY[K] in response
to the fourth node signal of the fourth node N4. For example, the carry pull-up part
630 controls the (K)th carry signal CARRY[K] as the first logic level in response
to the fourth node signal. In some embodiments, the carry pull-up part 630 includes
a second pull-up transistor TR6 and a third capacitor C3. The second pull-up transistor
TR6 can include a gate electrode connected to the fourth node N4, a first electrode
to which the first power voltage VGH is applied, and a second electrode connected
to a carry signal output terminal outputting the (K)th carry signal CARRY[K]. The
third capacitor C3 can include a first electrode connected to the fourth node N4,
and a second electrode to which the first power voltage VGH is applied.
[0095] The carry pull-down part 640 can pull down the (K)th carry signal CARRY[K] in response
to the third node signal. For example, the carry pull-down part 640 controls the (K)th
carry signal CARRY[K] as the second logic level in response to the third node signal.
In some embodiments, the carry pull-down part 640 includes a second pull-down transistor
TR7 and a fourth capacitor C4. The second pull-down transistor TR7 can include a gate
electrode connected to the third node N3, a first electrode to which a first clock
signal CKB is applied, and a second electrode connected to the carry signal output
terminal outputting the (K)th carry signal CARRY[K]. The fourth capacitor C4 can include
a first electrode connected to the third node N3, and a second electrode connected
to the carry signal output terminal.
[0096] The holding part 650 can maintain the fourth node signal in response to the second
clock signal CK. In some embodiments, the holding part 650 includes a holding transistor
TR3. The holding transistor TR3 can include a gate electrode to which the second clock
signal CK is applied, a first electrode to which the second clock signal CK is applied,
and a second electrode connected to the fourth node N4.
[0097] The stabilizing part 660 can stabilize the (K)th carry signal CARRY[K] in response
to the fourth node signal and a first clock signal CKB. In some embodiments, the stabilizing
part 660 includes a first stabilizing transistor TR5 and a second stabilizing transistor
TR4. The first stabilizing transistor TR5 can include a gate electrode to which the
first clock signal CKB is applied, a first electrode connected to the third node N3,
and a second electrode connected to a first electrode of the second stabilizing transistor
TR4. The second stabilizing transistor TR4 can include a gate electrode connected
to the fourth node N4, the first electrode connected to the second electrode of the
first stabilizing transistor TR5, and the second electrode connected to the carry
signal output terminal outputting the (K)th carry signal CARRY[K].
[0098] Although the example embodiments of FIGS. 5 and 7 describe that the shift register
unit 600A-k includes the second input part 610, the third input part 620, the carry
pull-up part 630, the carry pull-down part 640, the holding part 650, and the stabilizing
part 660, the shift register unit can have a variety of structures that can sequentially
output the carry signals.
[0099] The masking buffer unit 700A-k can output a (K)th sensing signal SEN[K]. Thus, the
sensing driving circuit can output the sensing signal SEN[K] to the (K)th sensing
line using the masking buffer unit 700A-k in the sensing period when the (K)th sensing
line is selected by controller. The masking buffer unit 700A-k can include a first
input part 710, a sensing pull-up part 720A, a sensing pull-down part 730, and a node
masking part 740.
[0100] The first input part 710 can apply the input signal (i.e., the sensing start signal
SSP or the carry signal of previous stage CARRY[K-1]) to a first node N1 in response
to a node driving signal SET and can apply a first power voltage VGH to a second node
N2 in response to the input signal and the node driving signal SET. In some embodiments,
the first input part 710 includes a first input transistor TR8, a second input transistor
TR9, and a third input transistor TR10. The first input transistor TR8 can include
a gate electrode to which the input signal is applied, a first electrode to which
the first power voltage VGH is applied, and a second electrode connected to a first
electrode of the second input transistor TR9. The second input transistor TR9 can
include a gate electrode to which the node driving signal SET is applied, the first
electrode connected to the second electrode of the first input transistor TR8, and
a second electrode connected to the second node N2. The third input transistor TR10
can include a gate electrode to which the node driving signal SET is applied, a first
electrode to which the input signal is applied, and a second electrode connected to
the first node N1. Therefore, when the node driving signal SET is applied to the first
input part 710, the first input part 710 can apply the input signal to the first node
N1 to output the (K)th sensing signal SEN[K].
[0101] The sensing pull-up part 720A can pull up the (K)th sensing signal SEN[K] in response
to a second node signal of the second node N2. In some embodiments, the sensing pull-up
part 720A includes a first full-up transistor TR13A and a first capacitor C1. The
first full-up transistor TR13A can include a gate electrode connected to the second
node N2, a first electrode to which the first power voltage VGH is applied, and a
second electrode connected to a sensing signal output terminal outputting the (K)th
sensing signal SEN[K]. The first capacitor C1 can include a first electrode connected
to the second node N2, and a second electrode to which the first power voltage VGH
is applied.
[0102] The sensing pull-down part 730 can pull down the (K)th sensing signal SEN[K] in response
to a first node signal of the first node N1. In some embodiments, the sensing pull-down
part 730 includes a first full-down transistor TR14 and a second capacitor C2. The
first full-down transistor TR14 can include a gate electrode connected to the first
node N1, a first electrode to which a first clock signal CKB is applied, and a second
electrode a sensing signal output terminal outputting the (K)th sensing signal SEN[K].
The second capacitor C2 can include a first electrode connected to the first node
N1, and a second electrode connected to the sensing signal output terminal.
[0103] The node masking part 740 can apply the first power voltage VGH to the first node
N1 in response to a masking signal MASK, and can apply a second power voltage VGL
to the second node N2 in response to the masking signal MASK. In some embodiments,
the node masking part 740 includes a first masking transistor TR11 and a second masking
transistor TR12. The first masking transistor TR11 can include a gate electrode to
which the masking signal MASK is applied, a first electrode to which the first power
voltage VGH applied, and a second electrode connected to the first node N1. The second
masking transistor TR12 can include a gate electrode to which the masking signal MASK
applied, a first electrode to which a second power voltage VGL is applied, and a second
electrode connected to the second node N2. Therefore, when the masking signal MASK
is applied to the node masking part 740, the node masking part 740 can activate the
sensing pull-up part 720A and can inactivate the sensing pull-down part 730.
[0104] FIG. 8 is a waveform diagram for describing a sensing operation of a sensing driving
circuit of FIG. 4.
[0105] Referring to FIG. 8, the display device controls a sensing start signal SSP, a masking
signal MASK, and a node driving signal SET to output the sensing signal to at least
one of the sensing lines in the sensing period.
[0106] For example, the third sensing signal SEN[3] is outputted to the third sensing line
in the sensing period to measure a characteristic change of the pixels connected to
the third sensing line. To output the third sensing signal SEN[3] in the sensing period,
a timing of the sensing start signal SSP can be adjusted. The sensing start signal
SSP can be applied to the sensing driving circuit. Each stage in the sensing driving
circuit can sequentially provide the carry signal to next stage. To activate the third
sensing signal SEN[3], the masking signal MASK is inactivated and the node driving
signal SET is activated at a point in which the second carry signal CARRY[2] is activated.
Therefore, the masking buffer unit of the third stage can receive the second carry
signal CARRY[2] and can output the third sensing signal SEN[3] in the sensing period
by controlling the masking signal MASK and the node driving signal SET.
[0107] FIG. 9 is a block diagram illustrating another example of a sensing driving circuit
included in a display device of FIG. 1.
[0108] Referring to FIG. 9, the sensing driving circuit 500B includes a plurality of stages
500B-1 through 500B-n that are electrically connected to each other. Each of the stages
500B-1 through 500B-n can include a shift register unit and a masking buffer unit.
The sensing driving circuit 500B according to the present exemplary embodiment is
substantially the same as the sensing driving circuit of the exemplary embodiment
described in FIG. 4, except that a substantially simultaneous driving terminal or
concurrent driving terminal GCK receiving a substantially simultaneous or concurrent
driving signal or global driving signal is added. Therefore, the same reference numerals
will be used to refer to the same or like parts as those described in the previous
exemplary embodiment of FIG. 4, and any repetitive explanation concerning the above
elements will be omitted.
[0109] Each of the shift register units 600B-1 through 600B-n can include an input terminal
IN, a second clock terminal CK, a first voltage terminal VGH, a second voltage terminal
VGL, and a carry signal output terminal CARRY.
[0110] Each of the masking buffer units 700B-1 through 700B-n can include an input terminal
IN, a first clock terminal CKB, a masking terminal MASK, a node driving terminal SET,
a first voltage terminal VGH, a second voltage terminal VGL, a sensing signal output
terminal SEN, and a simultaneous driving terminal GCK.
[0111] A simultaneous driving signal is for outputting the sensing signals that have substantially
the same phase to the sensing lines. The simultaneous driving signal can be applied
to the simultaneous driving terminal GCK. For example, the simultaneous driving signal
is applied to the simultaneous driving terminal GCK in an initialization period of
the display panel.
[0112] FIG. 10 is a block diagram illustrating a masking buffer unit of a (K)th stage included
in a sensing driving circuit of FIG. 9. FIG. 11 is a circuit diagram illustrating
a (K)th stage included in a sensing driving circuit of FIG. 9.
[0113] Referring to FIGS. 10 and 11, the (K)th stage 500B-k included in the sensing driving
circuit includes a shift register unit 600B-k and a masking buffer unit 700B-k.
[0114] The shift register unit 600B-k can provide a (K)th carry signal CARRY[K] to a next
stage of the (K)th stage 500B-k. The shift register unit 600B-k can include a second
input part 610, a third input part 620, a carry pull-up part 630, a carry pull-down
part 640, a holding part 650, and a stabilizing part 660. The shift register unit
600B-k according to the present exemplary embodiment is substantially the same as
the shift register unit of the exemplary embodiment described in FIGS. 5 and 7. Therefore,
the same reference numerals will be used to refer to the same or like parts as those
described in the previous exemplary embodiment of FIGS. 5 and 7, and any repetitive
explanation concerning the above elements will be omitted.
[0115] The masking buffer unit 700B-k can output a (K)th sensing signal SEN[K]. Thus, the
sensing driving circuit can output the sensing signal SEN[K] to the (K)th sensing
line using the masking buffer unit 700B-k in the sensing period when the (K)th sensing
line is selected by controller. The masking buffer unit 700B-k can include a first
input part 710, a sensing pull-up part 720B, a sensing pull-down part 730, and a node
masking part 740. The masking buffer unit 700B-k according to the present exemplary
embodiment is substantially the same as the masking buffer unit of the exemplary embodiment
described in FIGS. 6 and 7, except that the sensing pull-up part 720B receives a substantially
simultaneous driving signal GCK instead of a first power voltage VGH. Therefore, the
same reference numerals will be used to refer to the same or like parts as those described
in the previous exemplary embodiment of FIGS. 6 and 7, and any repetitive explanation
concerning the above elements will be omitted.
[0116] The sensing pull-up part 720B can pull up the (K)th sensing signal SEN[K] in response
to a second node signal of the second node N2. In some embodiments, the sensing pull-up
part 720B includes a first full-up transistor TR13B and a first capacitor C1. The
first full-up transistor TR13B can include a gate electrode connected to the second
node N2, a first electrode to which a simultaneous driving signal GCK, and a second
electrode connected to a sensing signal output terminal outputting the (K)th sensing
signal SEN[K]. The first capacitor C1 can include a first electrode connected to the
second node N2, and a second electrode to which the simultaneous driving signal GCK
is applied. When the masking signal MASK is applied to the sensing driving circuit,
the sensing driving circuit can output the simultaneous driving signal GCK as the
sensing signals to all of the sensing lines. Also, to output the sensing signal to
at least one selected from the sensing lines in the sensing period, the simultaneous
driving signal GCK can have a voltage level that is substantially the same as the
first power voltage VGH in the sensing period.
[0117] FIG. 12 is a waveform diagram for describing an initialization operation of a sensing
driving circuit of FIG. 9 in an initialization period.
[0118] Referring to FIG. 12, the display device controls a masking signal MASK and a simultaneous
driving signal GCK to output the sensing signals SEN[1] through SEN[N] that have substantially
the same phase to the sensing lines in an initialization period of a display panel.
[0119] For example, to initialize the display panel in the initialization period, the sensing
signals SEN[1] through SEN[N] are applied to the all of the sensing lines. For example,
a node driving signal SET is inactivated and the masking signal MASK is activated
in the initialization period of the display panel. The sensing pull-up part can be
activated and the sensing pull-down part can be inactivated. Therefore, the sensing
signals SEN[1] through SEN[N] that are substantially the same as the simultaneous
driving signal GCK can be applied to the sensing lines, respectively.
[0120] Although the example embodiments describe that the sensing signal is for measuring
a characteristic change of the pixel, the sensing signal is a gate signal for various
purposes.
[0121] Also, although the example embodiments describe that the transistors are implemented
as p-channel metal oxide semiconductor (PMOS) transistors, the transistors also can
be implemented as n-channel metal oxide semiconductor (NMOS) transistors.
[0122] The described technology can be applied to an electronic device having a display
device. For example, the described technology can be applied to televisions, computer
monitors, laptops, cellular phones, smart phones, smart pads, personal digital assistants
(PDAs), portable multimedia players (PMPs), MP3 players, navigation systems, game
consoles, video phones, etc.
[0123] The foregoing is illustrative of embodiments and is not to be construed as limiting
thereof. Although a few embodiments have been described, those skilled in the art
will readily appreciate that many modifications are possible in the embodiments without
materially departing from the novel teachings and advantages of the inventive technology.
Accordingly, all such modifications are intended to be included within the scope of
the present inventive concept as defined in the claims. Therefore, it is to be understood
that the foregoing is illustrative of various embodiments and is not to be construed
as limited to the specific embodiments disclosed, and that modifications to the disclosed
embodiments, as well as other embodiments, are intended to be included within the
scope of the appended claims.
1. A sensing driving circuit for a display device, comprising:
a plurality of stages configured to respectively output a plurality of sensing signals
and including a (K)th stage and a (K+1)th stage, the (K)th stage comprising:
a shift register configured to provide a (K)th carry signal to the (K+1)th stage;
and
a masking buffer configured to output a (K)th sensing signal,
wherein the masking buffer includes:
a first input circuit configured to provide i) an input signal to a first node based
on a node driving signal and ii) a first power voltage to a second node based on the
input signal and the node driving signal;
a node masking circuit configured to supply the first power voltage to the first node
based on a masking signal, and supply a second power voltage to the second node based
on the masking signal;
a sensing pull-up circuit configured to pull up the (K)th sensing signal based on
a second node signal of the second node; and
a sensing pull-down circuit configured to pull down the (K)th sensing signal based
on a first node signal of the first node, where K is an integer greater than 0.
2. A sensing driving circuit according to claim 1, wherein the first input circuit includes:
a first input transistor including a gate electrode configured to receive the input
signal, a first electrode configured to receive the first power voltage, and a second
electrode;
a second input transistor including a gate electrode configured to receive the node
driving signal, a first electrode electrically connected to the second electrode of
the first input transistor, and a second electrode electrically connected to the second
node; and
a third input transistor including a gate electrode configured to receive the node
driving signal, a first electrode configured to receive the input signal, and a second
electrode electrically connected to the first node.
3. A sensing driving circuit according to claim 1 or 2, wherein the node masking circuit
includes:
a first masking transistor including a gate electrode configured to receive the masking
signal, a first electrode configured to receive the first power voltage, and a second
electrode electrically connected to the first node; and
a second masking transistor including a gate electrode configured to receive the masking
signal, a first electrode configured to receive a second power voltage, and a second
electrode electrically connected to the second node.
4. A sensing driving circuit according to one of claims 1 to 3, wherein the sensing pull-up
circuit includes a first full-up transistor and a first capacitor.
5. A sensing driving circuit according to claim 4, wherein the first full-up transistor
includes a gate electrode electrically connected to the second node, a first electrode
configured to receive the first power voltage, and a second electrode electrically
connected to a sensing signal output terminal configured to output the (K)th sensing
signal, and
wherein the first capacitor includes a first electrode electrically connected to the
second node and a second electrode configured to receive the first power voltage.
6. A sensing driving circuit of claim 4, wherein the first full-up transistor includes
a gate electrode electrically connected to the second node, a first electrode configured
to receive a global driving signal, and a second electrode electrically connected
to a sensing signal output terminal configured to output the (K)th sensing signal,
and
wherein the first capacitor includes a first electrode electrically connected to the
second node and a second electrode configured to receive the global driving signal.
7. A sensing driving circuit according to any preceding claim, wherein the sensing pull-down
circuit includes:
a first full-down transistor including a gate electrode electrically connected to
the first node, a first electrode configured to receive a first clock signal, and
a second electrode electrically connected to a sensing signal output terminal configured
to output the (K)th sensing signal; and
a second capacitor including a first electrode electrically connected to the first
node and a second electrode electrically connected to the sensing signal output terminal.
8. A sensing driving circuit according to any preceding claim, wherein the shift register
includes:
a second input circuit configured to provide the input signal to a third node based
on a second clock signal;
a third input circuit configured to provide the second clock signal to a fourth node
based on a third node signal of the third node;
a carry pull-up circuit configured to pull up the (K)th carry signal based on the
fourth node signal;
a carry pull-down circuit configured to pull down the (K)th carry signal based on
the third node signal;
a holding circuit configured to maintain the fourth node signal based on the second
clock signal; and
a stabilizing circuit configured to stabilize the (K)th carry signal based on the
fourth node signal and a first clock signal.
9. A sensing driving circuit according to claim 8, wherein the second input circuit includes
a fourth input transistor including a gate electrode configured to receive the second
clock signal, a first electrode configured to receive the input signal, and a second
electrode electrically connected to the third node.
10. A sensing driving circuit according to claim 8 or 9, wherein the third input circuit
includes a fifth input transistor including a gate electrode configured to receive
the third node signal, a first electrode configured to receive the second clock signal,
and a second electrode electrically connected to the fourth node.
11. A sensing driving circuit according to claim 8, 9 or 10, wherein the carry pull-up
circuit includes;
a second pull-up transistor including a gate electrode electrically connected to the
fourth node, a first electrode configured to receive the first power voltage, and
a second electrode electrically connected to a carry signal output terminal configured
to output the (K)th carry signal; and
a third capacitor including a first electrode electrically connected to the fourth
node and a second electrode configured to receive the first power voltage.
12. A sensing driving circuit of claim 8, 9, 10 or 11, wherein the carry pull-down circuit
includes:
a second pull-down transistor including a gate electrode electrically connected to
the third node, a first electrode configured to receive a first clock signal, and
a second electrode electrically connected to a carry signal output terminal configured
to output the (K)th carry signal; and
a fourth capacitor including a first electrode electrically connected to the third
node and a second electrode electrically connected to the carry signal output terminal.
13. A sensing driving circuit according to any one of claims 8 to 12, wherein the holding
circuit includes a holding transistor including a gate electrode configured to receive
the second clock signal, a first electrode configured to receive the second clock
signal, and a second electrode electrically connected to the fourth node.
14. A sensing driving circuit according to one of claims 8 to 13, wherein the stabilizing
circuit includes:
a first stabilizing transistor including a gate electrode configured to receive the
first clock signal, a first electrode electrically connected to the third node, and
a second electrode; and
a second stabilizing transistor including a gate electrode electrically connected
to the fourth node, a first electrode electrically connected to the second electrode
of the first stabilizing transistor, and a second electrode electrically connected
to a carry signal output terminal configured to output the (K)th carry signal.
15. A display device comprising:
a display panel including a plurality of scan lines, a plurality of sensing lines,
a plurality of data lines, and a plurality of pixels;
a data driving circuit configured to output a plurality of data signals respectively
to the data lines;
a scan driving circuit configured to output a plurality of scan signals respectively
to the scan lines;
a sensing driving circuit according to any preceding claim; and a controller configured
to control the data driving circuit, the scan driving circuit, and the sensing driving
circuit,
wherein the plurality of stages are each configured to output at least one of a plurality
of sensing signals to at least one of the sensing lines so as to measure a change
in at least one characteristic of the pixels; and
wherein the (K)th stage includes:
a shift register configured to provide a (K)th carry signal to the (K+1)th stage;
and
a masking buffer configured to output a (K)th sensing signal, and
wherein the masking buffer includes:
a first input circuit configured to provide i) an input signal to a first node based
on a node driving signal and ii) a first power voltage to a second node based on the
input signal and the node driving signal;
a node masking circuit configured to supply the first power voltage to the first node
based on a masking signal, and to supply a second power voltage to the second node
based on the masking signal;
a sensing pull-up circuit configured to pull up the (K)th sensing signal based on
a second node signal of the second node; and
a sensing pull-down circuit configured to pull down the (K)th sensing signal based
on a first node signal of the first node, where K is an integer greater than 0.